1. Technical Field
The present invention relates to a photocurable ink jet recording ink composition and an ink jet recording method.
2. Related Art
Various systems have been utilized as recording methods of forming images on recording media such as paper based on image data signals. Among them, an ink jet system is an inexpensive apparatus and directly forms an image on a recording medium by discharging inks on a necessary image area only and therefore efficiently uses inks at low running cost. In addition, the ink jet system is low in noise and is therefore excellent as a recording method.
Recently, in the recording method of the ink jet system, a photocurable ink composition, which is cured by light irradiation, is used as an ink composition that can provide high water resistance, solvent resistance, abrasion resistance, etc.
For example, JP-A-11-302562 discloses a photocurable paint composition that contains 0.1 to 20 parts by weight of a thioxanthone photopolymerization initiator and 1 to 20 parts by weight of an acylphosphine or benzophenone photoradical generator based on 100 parts by weight of a coating film-forming binder component composed of 20 to 40% by weight of an acryloyl group-containing polyester oligomer having a number-average molecular weight of 2400 to 3150 or bisphenol A epoxyacrylate, 20 to 40% by weight of N-acryloylmorpholine, and 10% by weight of pentaerythritol triacrylate or dipentaerythritol hexaacrylate.
Unfortunately, when the photocurable paint composition described in JP-A-11-302562 is applied to ink jet recording, the composition causes problems, i.e., deterioration in discharge stability, deterioration in storage stability due to poor solubility of the photopolymerization initiator, and deterioration in curing property.